Low-pressure alarm for pneumatic tires



May`1, 1923. Y Y

w. H. BROWN LOW PRESSURE ALARM FR PNEIUMATIC TIRES sumisa may 1,1923. 'f t ASE?" imitan steer-ES?" PATENT M1-WWE l WALTER HENRY BROWN, or PAsAnnNA, entri#usuravl tow-PRESSURE stam/r ron rNnUiuAfrrc Trans.v

.. appuauon mea angustiosa, 1922. seriaiiv'o.' 584,132.

#To aller/:omit may concern:- practical embodiment of the ,invention"oper-V r le lit known that l', WALTER HENRY i atively applied to a vehicle wheel, only a` f BRowN, a citizen ot the United States, and'` fragmentary portion of theV latter` being; a. resident-foi Fasadenmin the county of Los shown,l i y 'y f t 60' angeles and State of California, have in- Figure 2 is a relatively enlarged'longi-Y #afented-certainnew and useful Improvements tudinalsection through the 'device detached: l in Low-Pressure Alarms v for Pneumatic from the wheel,'and illustrating the position y rires, ot which-th 'following is a specilicaof the valve comprised inthe device whenra :v tion. 1 predeterminedrminimum pressure has beenl 65 My invention relates to improvementsiu reached.A v I ffl low pressurealarms for pneumatic tires-and Figure 3 isaview Asimilar to Figure 2 it consists inthe combinations, constructions showing the position ofi the valves when and arrangements herein described andl the pressure within the ndevice is betweenv claimed. a predetermined low pressure and prede.- 70 The present invention is an improvement `terlillied minimum pressure, -on the low pressure alarm for pneumatic Figure/ 4; is va view similartov Figures :2 tires disclosed in my prior application for and 3 showing the position of the valves Letters Fatent or the UnitedStates, filed' when the pressure is *normaly or in other Qctobeyth, 1919', Serial Number 333,163 words above the predetermined low'v pres-l 75 In my aforesaid prior application, I dis- Sure, und A L closed a device attachable to a tire and hav- Figure 5is la transverse section through' aY ng means adapted 'to be actuated by air pres `iragmentaryportion of a,vehiclerwheel of a sure to cause an audible signal or alarm. to YAconstruction different from that illustrated i be givencontinuouslyiwhen a predetermined in Figure l and through aportion of a modi-l 80 low pressure has been reachedin a'tireuntil fied form of the' device, aportion of the mod- Qa still lower pressure has been reached, and `iied form of the,devicebeingishownin side'v 'i 2211.1

to prevent further escape of air fromv the tire eleVtOn. y Y through the device when the last named or Referringnow to thejdrawings` and par' lowest pressure is reached,valves being piroticularl'y yto Figures 2, 3 and Il thereot, the "85 l 3G vided in the device to control the flow oi' air present invention contemplates theA pro-'y4 therethrough. f v n' vision o-a vsubstantially cylindrical bodyfi :in object et the present invention is to havinga nipple portion 2 extending laterprovide a device of the character described ally' tl'leretrom at'a point somewhat. nearer in which means are! provided for utilizing one end than the' other.` Thebore `8 ofthe' 90 to ya' relativel great degree theair pressure nipple 2 is reduced at d'tofprovidevanopen#- withinthe c evice to move Y and hold the ing or port of restricted area throughlwhich y valves supportedl therein againstor away Ithe bore of' the' nipple'. communicates with from their Seats, i' i y' v the inteI'iOI Of .tlle'lody l. SBCOIid'iiipple I A still further object o the'present invenportion' fextends Alaterally from the bodyV 195? 40 tion isto provide a device of the character ina. position correspondingl to that of the 5 described which' comprises positively acting nippleQ in so Ja'r as its rotation between the' means Jor controllingthe -'flow of pressure ends of the body is concerned, the nipple .5 y luidy therethrough Vand means or mountingl preferably'being'.diametrically opposite the the device on a vehicle wheel in such man- ,nipple'f' Thenipple" 5 has ay bore dre-y 100 ner as to preclude any appreciable effecten duced at 7' topprovide la port or Vopeningot l i the action of the pressure iuid iow controlrelatively "small area in'cross section through ling means because Vof centrifugal action setl which the bore 6 is in communicationfwith up by the rotation ot the wheel.`vv f the interior of the body. ln the construc-y g Otherobjects and advantages will be aption shown, the openings y7; and 4 are'axially "105 parent Jfrom the following description` and aligned with each other.` i` g n the novel features 4of the invention willoe The'jnipple" 2 is adapted.'iorfconnection j f particularly outlined inthe appended claims. with the usual valve stem of a pneumatic` My invention isillustrated in they accomtire. A valve stem .is shown in Figure l 'as v panying drawings, forming a partof this extending'throughanopening inthe'felloev U0.' application,` in 'hich- 9 ot wheel upon which the tire provided` Figure 1 'is a side elevation showing with the' valvestem 8 is mountedand the Y l2 and has ving 1 Vport 7 through which nipple 2 which in the present instance is provided with external screw threads is connected with the valve stem 8 byy the coupling 9 which may be of any suitable or preferred form, such as that illustrated to advantage in Figure 5, whereby the body 1 will be supported between adjacent spokes ot the wheel 9 with the longitudinal axis thereof extending in a plane parallel with a plane passing through the outer periphery oi" the tire on the vehicle at the point oi contact of the latter withA a surface traversed, or in other` words the longitudinal axis ot' the body 1 will always be horizontally disposed during the rotation ofthe wheel. The body 1 is illustrated in the drawings as being' supported with the longitudinal axis thereoiQ parallel with the axis about which the wheel 9 is adapted to rotate. i

The nipple 5 is adapted to threadedly gage they end portion of the casing ot usual Schraeder or like valve 11.

A third nipple or tubular boss l2 extends laterally from the body l, preferably along' the side oi the nipple 5 so that the proximate walls of the nipple 5 and the nipple 12 are integral with each other. The bore or the nipple l2 is reduced at 14 so as to be equal in cross sectional area with the bore 15 of a radial inwardly extending valve post 16 which extends from the inner wall ot the body 1 in axial alignment with the nipple a length slightly greater than that of the radius ot the cylindrical chamber or bore of the body l. The bore .15 is in communication at its inner end with the interior of the body 1 through lateral open- 7, the walls of which are beveled adjacent to their ends, as indicated at 18 to provide a seat for a valve 19 which is supported for cooperation therewith in a manner which will be hereinafter set forth. The lateral opening or port 17 is concentric with the inner wall of the body 1.

A partition dividingr the interior `ot the body 1 into two chambers, indicated at 20 and 2l respectively, is provided by a disl: 22 having threads on its peripheral wall engaged with threads on the inner tace of an integral annular enlargement 23 which is formed on the inner wall ot the body 1 between the valve post 16 and the opening` or the nipple 5 ycommuni- Cates with the body. lt will thus he appar` ent that the nipples 5 and 2 will be in com# munication with the chamber 21-wliile the nipple 12 will be in communication through the bore of the valve post iti and the lateral opening or port with the Ichamber .20.

A whistle cap 23 having a relativelyv small central opening or orice 24 extending through the head thereof in threaded engagement with the bore 18 oft the nipple 12.

- The body l is provided with counter bores enthe 24 and 25 respectively at the opposite endsk thereof and these counter bores are adapted to receive diaphragme 26 and 27 which are releasably held clamped against the inner ends @t the counter bores by retaining bush-V which are in threaded engagement adjacent to their inner ends with the respective counter bores and extend bel yond the opposite` ends of the body `l as shown. The diaphragme 26 and 27 are similar in construction, each having' a central opening therethrough and each being' 'formed with a series of concentric annular corrugations therein. A rod 29 extending through the central opening of the diaphragm 26 is secured to the latter intermediate ot' its length in any suitable manner, as by means of nutsBO screwed thereon into clamping relation to opposite diaphragm. The .arrangement is such that an air tight connection is provided between the rod 29 and the diaphragm 26 and the end portions of the rod 29extend laterally4 ot opposite sides of the diaphragm, thewrod 29 being held against any appreciable move ment independent of the diaphragm. .A

sides of the y rod 29 at the inner end of the latter and is in sliding contact withthe lower end portion of the valvevpost 16.

The yoke or frame 31 carries a valve 19,` the arrangement being such that wheny the rod 29 is moved axially-toward the dislrv22', the valve 19 will be moved from its seat` and when the rod 29 is moved axially in the opposite direction, the valve 19 will be moved against the seat- 18 and the opening 17.

A valve 32 carried at the inner end of a rod 33 extending through the centraliop-ening of the diaphragm 27 and being secured to the latter by clamping` nuts 34, is adapted to seat in a beveled or enlarged end portion 35 ot a central opening through the disk'22.

A disk 37 ycarried on the outer end portion of the rod 29 is reduced diametrica-flly at 38 f to `accommodate the one end of a coiled spring- 89 which is supported atits other or outer end upon a central boss-40whichgextends inwardly from' a' plug` 41 which is screwed into the one retaining bushingor ring 28 and closes the outer end of the latter. A screw cap 42 isr'tittedupon lthe end ot the bushing 28 in which the yplugrl-l` is` disposed. The cap 42 -is provided with a central opening 43 and the plug 4l is pro in position to close ,vided with openings 44 therethrough, where- (ill tainingjbushing or ring 28 outer endv of` the latter.y The plug 45 is formed with a central inwardly extendingalli boss 4T Whichsupportsthe outer endof coiled spring 48,the inner end of Which is supported upon'a reduced end portion 49 of -a' disk 50 which is in threaded-engagement with the outer end portion of then rod 33. screw cap 51 is `fitted upon theouter the retaining bushing 28 inv endv portion of which the plug45'is -disposed, and has a cen'- tral orifice'52v therethrough.` l

From the foregoing description of the it is desired to inflate Aa service connection sure'is attachedA to 11. The springs 48 and 39 are `expansion springs and the valve 3E2fvvill thusl be held in positionto close the opening 36by. the action of the spring 48 atthe beginning of the operation of inating the tire. ln consequence, air enteringythe chamber 2O yWill pass through the nipple '2 into the tire. n, As pressure buildsup Within flexed outivard and the valve 32 will' beA openedV against the' action .of the spring 48. lf, at this time, whistle' cap 23 is closed,`as by being' by the finger of a hand, pressure Will'build up within thechamber 2O until the diahragm 26 is 'actuated tov of the valve 19 kagainst theV action ofthe spring 39. In 'Figure 4, thevalves 32 and 19 are shovvn `in the `positions which they Willassume when normal Working pressure;

is maintained Within avtire to which attached. It is to'beunderstood that the usualy Vvalve connection of the valve stem of the tire has` been removed before theV device is attached thereto.` 'i

For convenience yin tion of the device,H the normal Working pressure ofva tire to Which the device is attached is approximately 60 lbs. per square 'inch an Warning is desired, if because of puncture,

sloiv leak or other cause the pressure dropsto 5() lbs. per square inch; Thespring 39 is adjusted so that it will elongate orv expand when the air pressure against the diaphragm 26 has dropped to 50 lbs. 26 is flexed under the pressure applied thereto by the expanding spring, the valve 19 is moved lto open position, as. illustrated in Figure 3` and air isl permitted to pass through the bore 15 of the valve post into and through the orifice of the Whistle cap 23, thereby causing a Whistling sound whic gives Warning to sure Within `the inc li or less. The Warning is given continu` adj acent tov the the tire and Within the chamber 21the diaphragm 2 will be A;

' "The diaphragms Vcomprised have concentric annular corrugations there-kv the orifice 24through the n great flexure is possible@ i 'coveredVv` i l cause the closingv positions in the capingV pressure fluid. ,pressure Vfrom a source 4 the device is appliedtends to hold thfvalves '105. l

explaining the operav it Will kbe assumed that the diaphragm 27 d that a' As the diaphragml determined distance it ,thema as. the operator that the prestire is 50 lbs. per `square,

`ously until which' moving` the valve32 to closed position and thus preventingthe furtherA escape of yair y 'The springs 4,8 and`v39r may be adjusted throughthe V'Ni from the tirethroilgh the body.

agency of the adjustingplugs k45`faiid 51 to expand against predetermined air,pressures,',` theligures' 50 lbs. and

the device l,for operating lthe valvesjin Conl the pressurel Within the tire has' 'reached La still 'lowerv` or: 'minimumv pressure, is assumed to-be '40vlbs. perfsquare r iitthat time, the spring 48 will ex-wy pand andV Will flex the diaphragm 27 thereby i 'l0 f A '49 lbs. recited' herein `being 'onlyfillustrative and* not restrictive.y rllie diaphragmv construction 'comprised' inv ljunction with the; springs insuresjfpositive",'4 actuation of 'the valves which areheld more Y' securely in desired positionsbecause of given air vpressures than is the valvesfr'om open vice versa.A lifloreover,`

a valve operating ar-l I vpossible when springs alone' are employed to effect movementl of.. to closed position, and

rangement includinga diaphragm, such fas' I illustrated and described, Willueffect move-*f 1o througho,ut an extended `period"fof service than is possiblefwith a valve'foperating con-4 y I struction in Which'the diaphragin isvomitte'ld.

in 'so that vrelatively in the device ivhena dia hragmof'afgivenfsize isem-' i ployed. y 'Itis' the valves '19 and 321move tovvtheirk closing in closed positions. in consequence, the pres'- `direction 'of currents',4r of ,es-v A s l'Ihatis-to say, thev of pressure to vv vhich sure against the valves themselve'stends to v aid the `means provided by my inivention-fand 1 hereinb'efore described for .moving and ing the'valves against their seats.

Itis also to be observedl that the disk 3'! and the diaphragm 26 andthe disk 50.- and that the diskl 37 serves to reenforce or sup,v port the flexed diaphragm position in suoli are vrelatively arranged so v n 26, particularlyY after the valve 19has been moved to closed manner as `to preclude over Vdeect-ion or undue strain of the diaphragm 26, andthe diskO performs' a The bosses 49 and 47 are axially alinedv and in confronting relation in respect toV each other. rllhesenbos'se's constitute coopera- 'tive-stop lmembers-vvluich Contact -each other when the rodV 33 has been movedV axially a the diaphragm 27 to prevent over :inv Figure' -5 the nipple ,form of the .device .replaced by 'a nipple portion 6()vr which exlike function 'inrespect to thediaphragm 27.

because of pressure ,oni

travel ofvv v12o 125 j portion 2 of thev `heretofore' described is tends substantially at right angles to the nipple 5 and isrelativelyv long, being bent laterally. at a determined distance from ,its extremity to provide an attachin. r portion 5r-61 Whichis adapted vfor the agency ofthe coupling l() with the valve stemv of al tire mounted upon a Wheel 62. The wheel 62 represents any wheel, the spokes or Web portion of which is conlozstructedinsuch manner as to preclude the positioning oi the body in the posit-ion in which illustrated in Figure l. For example, the Wheel 62 may be of the disc-vvheel type of construction. Ineither case, thefbody of 15:;thedevice is positioned so that the aligned axes of thes'prings) and 48 lie in a plane parallel Witha plane passing ythroughxthe peripheral portionrof the tire therefore consider as mv own all modifications of theform of the d evice herein disclosed which fairly lfall Within theappended claims. p

claim:` l v i l. Ina loW pressure alarm, a casing' attachable to a source of pressure, and pro vided With an outlet, a valve disposed Within the casing for controlling communication (ygbetweenY the source of pressure and the outlet, a springreacting aga-inst the valve rto tend Ato hold the latter in -openV position, a diaphragm supported within the casing and connected With the valve to move the latter the scope oi attachment through Y on the Wheell whichV is in Contact with a suriace traversed.y

` spring reacting ythe second named providedwith anoutlet, Aa valve disposed.A Within Vthe casing` for controlling coinmuiiiration between rtliesource. ot' pressure and the outlet, valve to tend'tohold the latterin open posir tion, a diaphragm supported Within the cas ing and connectedwithl thevalve to move.

the latter toclosed position When-the diaphragm is actuated by definite. fluid pressure, a-second valvedisposed Withinthecasa soriiio'i'reactine awainstv the :n n. :s

ingl and controllingV communication vbetiveei.I

the i'irst valveand the source ofpiessure, a against the second valve tending to hold it in closed position, and a second diaphragm supported Within `the casina' and connected with the second valvey for moving the latter rto open. position when diaphragm is actuated by a deifinite iiuid pressure.-

8. A- device ot the character comprising` a casing attachable to oi' pressure and provided With Vandescribed a source ot pressure and the outleta springireactin` against the valve to tend tohold the latter in open position,y a diaphragm supported Within 'the casing and connected With thi valve tofmove theflatterto Iclosed position when the diaphragmis actuated byka defi'- iiite fluid pressure, and

disposed -Within the casing" communication vbetween said outlet. y

VALTER HENRY BROWN.

for controllingf valve and the l outlet, ay valve disposed Within the casing' for con-l trolling' communicationbet-Ween the source differentialv means; 

